Protection Function Logic
283
7UM62 Manual
C53000-G1176-C149-3
that can initiate trip signals, as well as for trip signals that are initiated using the device
function controller.
2.44.3 Fault Display on the LEDs/LCD
2.44.3.1 Principle of Function
The storage of messages masked to local LEDs, and the maintenance of spontaneous
messages, can be made dependent on whether the device has issued a trip signal. In
this situation, these messages are not issued, if one or more protective functions have
only picked up on a fault, but a trip signal has not been issued yet by the 7UM62
because the fault was cleared by another device (for instance outside of the own
protection range). These messages are then limited to faults in the own protection
range. Figure 2-132 illustrates the creation of the reset command for stored
messages. By the moment of the device dropout, the stationary conditions (fault
indication with excitation/with trip signal; tripping/no tripping) decide whether the new
fault remains stored or is reset.
Figure 2-132 Creation of the reset command for the memory of the LED and LCD messages
2.44.3.2 Settings
Pickup of a new protective function generally turns off any previously set light displays,
so that only the latest fault is displayed at any time. It can be selected whether the
stored LED displays and the spontaneous messages on the display appear upon
renewed pickup, or only after a renewed trip signal is issued. In order to enter the
desired type of display, select in the
SETTINGS
menu the sub-menu
Device
. Address
offers the two alternatives
Display Targets on
every Pickup
and
Display Target on TRIP only
.
Addr.
Parameter
Setting
Default Settings
Comment
0280
0.01 .. 32.00 s
0.15 s
Minimum duration of the trip
command
&
Relay TRIP
”1”
Trip Signal drop out
Reset LED and LCD messages
Targets on every pickup
Targets on TRIP only
Addr.
Parameter
Setting
Default Settings
Comment
Display Targets on every
Pickup
Display Targets on TRIP only
Display Targets on
every Pickup
Fault display on the LEDs/LCD